Connecticut Arms Against Mosquito-Borne Virus

Published: September 8, 1996

MYSTIC, Conn.—
Connecticut health officials are taking precautionary measures to prevent the spread of Eastern equine encephalitis, a deadly mosquito-borne virus that has been found in insects in neighboring Westerly, R.I., as well in central and eastern Long Island.

Gov. Lincoln Almond of Rhode Island declared a state of emergency in Westerly on Thursday, after state health officials announced that monitoring indicated the presence of the virus in 1 of every 100 mosquitoes. Aerial spraying to kill the larvae began on Friday.

Last week, Connecticut officials set traps in the eastern parts of the state, focusing on cedar swamps in Stonington, North Stonington and Voluntown that provide the right breeding conditions for mosquitoes.

A spokesman for the Connecticut Department of Public Health, Mark Brennan, said that precautionary ground spraying to kill adult mosquitoes would begin in Stonington and that mosquitoes collected from traps would be sent to Yale University for testing. Test results are expected by midweek.

''At that point,'' he said, ''we will determine if more spraying is necessary.''

On Long Island last month, several parks were closed and sprayed after Dr. Mary E. Hibberd, Suffolk County's Commissioner of Health Services, declared a public health threat because the virus had been isolated in four mosquito samplings at Southaven Park in Yaphank.

Stonington officials have closed public parks early and late in the day, when the insects feed. Next week, the school day in Stonington, North Stonington and Westerly will begin at 9:30 A.M., an hour and a half later than usual, to reduce risk of exposure in playgrounds.

Health officials have urged residents to take precautions by staying indoors during high-risk hours and wearing long sleeves, pants and insect repellent when outside in the early morning or at dusk.

The North Stonington First Selectman, Charles Elias, said he had been advising concerned neighbors to take the recommended precautions.

Eastern equine encephalitis is a rare viral disease that can cause paralysis in humans. The disease is spread among migrating songbirds by virus-carrying mosquitoes that bite birds but not humans. It is transmitted to humans by mosquitoes that bite both birds and humans. The virus is also a major threat to horses -- hence its name.

The disease, for which there is no remedy, attacks the brain and spinal cord and has a 30 percent mortality rate; of those who survive infection, 50 percent suffer long-term nervous-system damage. No cases have been reported in Connecticut; in 1990 there were three reported cases in Massachusetts. The virus has also been found this year in mosquitoes in Alabama and Florida.